HAVANA (AP) — It was a day when Cubans were called to speak with one voice to demand the return of intelligence agents serving long prison terms in the United States.

Then, at a nationally televised event outside the U.S. diplomatic mission in Havana, a prominent musician sang not only about the so-called Cuban Five but also his wish for more freedom of information and direct presidential elections.

Artists, writers and musicians have long enjoyed a certain amount of room to speak critically about the island’s Communist system. But Robertico Carcasses’ unusually bold lyrics at the pro-government concert-rally were the talk of the town on Friday.

Carcasses, the 41-year-old leader of the Cuban jazz-fusion combo Interactivo, sang about his desire for “free access to information so I can have my own opinion…”

“I want to elect the president by direct vote and not some other way,” he continued.

“Neither militants nor dissidents, (we are) all Cubans with the same rights.”

“And an end to the blockade,” he added, in reference to Washington’s 51-year-old economic embargo against Cuba, “and to self-blockade.”

Then, more in line with the theme of the event, he gestured at the U.S. Interests Section behind the stage and exclaimed, “Free the Five Heroes!”

“When I heard the first line, I thought, ‘Did I hear that right?’” said Diego Ferran, a 68-year-old retiree who watched the performance on TV.

“I was surprised that that was being shown on television … I was very pleased that he would do that, and in that place right in front of the Interests Section,” Ferran said. “He’s very right in everything he said.”

A woman who answered the phone at Carcasses’ home Friday said he was away, and calls to his cellphone did not go through.

His lyrics alluded to authorities’ control over many aspects of society.

The state and Communist Party operate nearly all island media, and Internet access rates are very low, if creeping upward.

The Communist Party is the only one allowed in Cuba, although membership is not a requirement to run in elections. The president is selected not by direct popular vote, but by parliament, which in turn is elected on a ballot with just one approved candidate for each seat. Cuba defends its political system as more participatory and democratic than most others.

Other prominent musicians have tested the boundaries of acceptable speech.

Legendary crooner Pablo Milanes has given interviews in which he criticized counter-protests that are quietly encouraged targeting anti-government groups such as the Ladies in White.

Singer-songwriter Silvio Rodriguez has also suggested that dissidents’ freedom of expression should be respected, even if their opinions aren’t shared.

Groups such as rappers Los Aldeanos pull no punches in criticizing the government, but unlike Carcasses, they are outside the island’s music establishment and don’t appear at official venues.

In 2008 punk rocker Gorki Aguila, known for raunchy lyrics targeting Fidel Castro, was convicted of public disorder and fined, although prosecutors dropped a “social dangerousness” charge that could have resulted in a long prison sentence.

Carcasses’ lyrics were perhaps most remarkable for where they were delivered.

The concert was the crowning event of a government-sponsored yellow ribbon campaign to raise awareness about the Cuban Five, who were convicted in 2001 of spying on U.S. military installations and exile groups.

Cuba maintains that they were only monitoring violent exile groups to prevent terror attacks on the island, and their imprisonment is one of Havana’s chief grievances against Washington.

Fans packed the so-called Anti-Imperialist Plaza at the foot of the U.S. Interests Section Thursday night to hear more than a dozen performers. One after another, they demanded freedom for the four agents still behind bars.

As the show drew to a close, Carcasses rose from the piano during a part of the song “Cubanos por el Mundo” where he commonly improvises. Standing beneath some two dozen fluttering Cuban flags, Carcasses sang to the crowd and viewers back home about what was on his mind.

“It was right at the end of the concert. Everyone was singing and dancing, and I think not everybody realized what he was saying. I think that’s why more people weren’t shouting when he said it,” said Maite Delgado, a 49-year-old office worker who was at the show.

“But I thought it was great that he did because he was absolutely right,” she said, “and I wish more artists would say more things like that so we can keep moving forward.”

Others were not amused.

“Unfortunate and opportunistic as well as disrespectful performance by Robertico (Carcasses),” Edmundo Garcia, a Miami-based journalist and activist sympathetic to Cuba said via Twitter. “But one swallow does not a summer make.”